Pulse amplitude analyzer



Oct. 22, 1957 G. w. GRAY ErAL 2,810,828

PULSE AMPLITUDE ANALYZER Filed Oct. 27, 1953 INVENTORS 11./ fy .I einen MOREY Unite States Pater 2,319,823 Y Puten aMrLrrUnE ANALYZER George W. Gray, Lambertville, and Arthur S. Jensen, Princeton, N. E., assignors, by mesne assignments, to the United States of America as represented by the United States Atomic Energy Commission Appiication ctober 27, i953, Serial No. 338,632

7 Siaims. (Ci. 25d- 27) This invention relates generally to pulse amplitude analyzers. More particularly, though not exclusively, this invention relates to apparatus for sorting and counting a series of pulses, such as provided by a scintillation detector when exposed to the products of nuclear disintegration, for the purpose of determining the distribution of these pulses in amplitude.

In several iields of investigation, particularly in that part of nuclear physics wherein beta ray and gamma ray spectra are of importance, it is necessary to analyze the amplitude distribution of a long series of pulses. In nuclear work, these pulses may be derived from the output of a photomultiplier as a result of scintillations caused by the energetic nuclear particles incident upon a fluoresentcrystal, such as anthracene, sodium iodide, and the like. Each nuclear particle gives rise to a train of scintillations; each scintillation being a result of one atomic reorientation in the crystal. Since the nuclear scientist is interested in the energy of the nuclear particle, and since this energy is proportional to the number of such reorientations, the light energy caused by one incident particle must be integrated into a single voltage pulse. The pulse amplitude analyzer, in accordance with the present invention, receives only this single pulse per incident nuclear particle.

:it has been proposed to build pulse amplitude analyzers of the type using a cathode ray tube having a plurality of targets. In this prior art apparatus, the pulse to be measured is applied to the deflection plates of the cathode ray tube in order to deect the resultant electron beam an amount proportional to the amplitude of the pulse. The targets of the cathode ray tube are positioned in linear alignment with respect to each other along a line perpendicular to the electron beam. The particular target which receives the beam current is connected to recording means for indicating the amplitude of the pulse being measured. These prior art cathode ray tubes, and their associated circuits, present difcult problems in design and construction. The focussing and deflection sensitivity must be quite critical in order to avoid beam current striking more than one target for any one pulse being measured and to obtain reasonably accurate results.

There are also systems intended to reduce the bandwidth of television signals so that there may be used means of transmission, which are restricted in their frequency response, without loss of detail in the picture. Some of these systems require that the original television signal be sampled at certain instants of time and that Jthe thus sampled signal be modified in accordance with its amplitude. A pulse amplitude analyzer is required to measure and channelize such sampled signals for modiiication. Such a pulse amplitude analyzer must be capable of measuring these signals, with reasonable accuracy, when their repetition rate may exceed million pulses per second.

One of the major problems in the design of a pulse amplitude analyzer is the determination of the interval ice of, time during which the pulse is near its peak value. In most of the prior art analyzers, these intervals of time are precalculated from the time constant of an integration circuit, and the analyzer is rendered -operative during these preset time intervals. The pulse amplitude, however, is not constant but, in fact, does change during that interval of time with the result that often one pulse activates two of the analyzers amplitude channels simultaneously, and causes an error in sorting and counting.

It is, therefore, a principal object of the present invention to provide an improved pulse amplitude analyzer having features which will overcome the above-mentioned difticulties and disadvantages.

It is another object of the present invention to provide an improved pulse amplitude analyzer which will analyze a series of pulses and provide a measure of their distribution in amplitude.

Still another object of the present invention is to pro-V vide an improved pulse amplitude analyzer using cathode ray tubes of relatively simple design and construction, and employing associated circuitry permitting the deilection sensitivity of the cathode ray tube to be much greater than in prior art analyzer systems. Y

A further object of the present invention is to provide an improved pulse amplitude analyzer wherein nonlinearities in the input circuits can be compensated, wherein the defocussing and rate of change of the deection sensitivity with delection of the beams of the cathode ray tubes do not affect the operation of the system, and

wherein the cathode ray tube beam currents need not be precisely constant.

Still a further object of the present invention is to provide an improved pulse amplitude analyzer wherein no part of the circuitry need be 1of any Wider bandwidth than that required to pass the unknown pulses accurately, thereby resulting in a system which can be extended to relatively high pulse repetition rates.

According to the invention, these and other objects and advantages are attained in an improved apparatus for sorting pulses of voltage of diierent amplitudes into separate channels, whereby each channel will receive pulses of substantially the same amplitude, and for counting the pulses in each of the channels. A pulse of unknown amplitude, which is to be sorted and counted is fed from an integrating circuit into a driver amplifier, the last stage of which is ycarefully D. C. restored. The output of the driver amplifier inserts the pulse into a main, multi-section transmission line whose shunt capacitors may be the deflection plates of cathode ray beam deflection tubes. Each section of the main transmission line comprises a cathode ray tube having an electron gun, a pair of electrostatic deection plates, and a collecting target whose lower edge is the mean position of the electron beam when the difference in potential between the deection plates is zero. One of the dellection plates of each cathode ray tube in each section in the main transmission line is biased progressively less positively in such a manner that a pulse travelling down the main transmission line will deflect upon theirrespective targets the beams of all of the tubes for which the amplitude of the pulse exceeds the bias. The order number of the lirst cathode ray tube whose beam is so deiiected is proportional to the dijerence between the pulse amplitude being measured and the maximum amplitude acceptable by the apparatus, due allowance being made for attenuation of the pulse by the main transmission line. An output signal derived from the first cathode ray tube, in one of the sections of the main transmission line, that becomes conductive is applied to a triggered control pulse generator. The shunt capacitances in the main transmission line may be the input capacitances of any well known 'threshold circuits, for example, monostable multivibrators, whose thresholds are set by appropriate biasing method progressively closedy to the D. C. restored-reference level.

. Eachof these threshold circuits in itsvturn will activate its"a`ssociated"trigg'ered co'ntrol pulse generator or the out-Y put-of. the threshold' circuit itselfmay be the-triggered condol pulse`.".l`here'sultant controlled pulse'is inserted into va control transmission line running parallel tothe mainltr'ansmission line; The-control transmission lineV comprises" aV series 'of sections/each having 'a cathode coupledfampliiier, or other unidirectional device, and a section' of delay'line combined 'to form a transmission line withjvery'little; if any, 'attenuation for signals travelling in""onedirection, but 'with Vvery great attenuation for signalsltravelling in the opposite direction. The constants of Athe circuitsA are chosen so that the delay time per sectionfisthe samer'in both-the main transmission line and Vtheco'ntrol transmission line. The main transmission line Y and the' controlt'ransmission line are interconnected by circuit means by means of which the beams-in the cathode ray tubes' subsequent 'to the cathode ray tube rendered conductive-bythe-unknown pulse areV cut on. Therefore, for each unknown pulse inserted into the main Ytransmis'sionline'byithe driver amplifier, one and only one,

Vcathode ray tube is rendered conductive. VThe output of the conducting cathode ray tube forms a control pulse in" thecontr'ol transmission line to prevent the unknown pulse, asit continues down the main transmission, from renderinganyV other cathode ray tube conductive. The output'from the triggered control pulse generator also actuales a; respective sealer and counter circuit associated with each section of the main transmission line.

The'riovel features'of. the invention, aswell as the invention itself, bothras to its organization and method of Y operation' willbe understood indetail from the follow- Energy resulting 'from the nuclear disintegration of a -nuclearparticlefrom the source 10 is`detected by a scintillati'n crystalidetectc'n'rV 12,Y wherein a crystal ofV anthracene, sodium iodide; or .the like, is caused to scintillate, in `a manner well known in the art. These scintillations Vare .directed toia photomltiplier 14,Y and the current therefrom isappliedto an integrator circuit4 16 to form a voltage 1 pulse. 1 'In this manner, the energy of a single nuclearlparticle, as for example, a beta particle is detected Y Vandintegrated into a single pulse. The. pulse amplitude analyzer, in`a`ccordance with vth'e'pres'ent invention, re-

ceivesonly onei pulse perincident nuclear particle.v The shape Vof'this zplse is determined largely by the constants ofv thefintgrating circuit 16.l Y

- The outputplllse from,V the integrating circuit 16. is fed to a driver amplierlSl where it isamplied. The last stage of 'the driver amplifierxlS is carefully D. C. restored to a` reterencepotentialby a D'. C. restorer 20, of conventional design, sothat'all `pulses will havev their ampli.- tudes measredtroni this reference potential;v `The D. C. restoredoutput'pulse, Whoseamplitude isto be measured,

is appliedto the-input terminal 22 of a main transmission.

linej 24, 'of low loss, and` good frequency 'and' 'phase .characterlsticstf Y Thel mainjtransrnissionline 24 comprises aof Ysfrrctions each offy which has an'inductan'ce]A 26, v28, 30,V

etcnfrespectively,,and-.a cathode-ray` tube 36, 38, k40,'etc.,

espantar-f While. only three SefiQS-Qf 111e maia sans mission line 24 are illustrated, for the sake of simplicity, it is understood that there will-be as many sections inthe transmission line as the numberof channels into which the train of pulses of unknown amplitude are to be sorted and counted.k The shunt'capacitor for the lrst section of the transmission line '24 is formed by the deflection plate 42 of the cathode ray tube 36.Y The upper plate 42 is connected'to a point intermediate 'the ends ofthe inductance 26, and the` lower plate 44 of the tube 36 isV connected to ground through ythe movable vtap onY a p0- tentiometerY 46. A` source of voltage (not shown)Y is connected across the potentiometer 46 in order to biasV theV deection plate 44 positively withirespect to ground,

for the purpose hereinafter appearing. 'Ihe plate44 is also bypassed'to groundbya bypass capacitor 48.

rille sections of the transmission line 24 are connectedV to each other by connecting the inductances 26, 28,:30,j

etc. in series. The transmission line 24 is terminated by connecting .itto a source of unidirectional potential (not 'shownl through an appropriateterminating perlance't).V The transmission line 24 is appropriately terminated in order to prevent unwanted reections, in aY manner well known in the art. The cathode ray tube V36 comprises the usual Yelectron gun' having a cathode 52V and acontrol grid 54. Y.The cathode 52 is connected to a source of filament voltage (not shown) and to the negative terminall of a source of voltage (not shown). The cathode 52 is connected` through a resistor 56 to the grid S4, and is bypassed to ground by capacitor V58. A first anode `60, a second anode 62, and an accelerating anode 6470i the cathode ray tube 36 arereach connected` to sources of'operating potential (not shown), ina manner wellwknownin the art.'-Y target 66 is positioned within' theevac'uatedenvelope of the. cathode ray tube 36 so that its lower ,edge 68 will just intercept the electron beamV of the,Y tubef36 when the difference in potential between the deiiection. plates 42u and 44 is a predetermined value,

' sion line 24 the electron beams inl all of the. cathode ray t tubeswill be deected downwardly so that they will impinge upon the electrode's'64, 86,.88,.etc. of the-'tubes Vsay. zero. The'target 6 6 is'con'nected to a source of positive potential 'through a load resistor v70,V and to a triggered control pulse generator 72, for the purpose hereinatter'appearing. Y

The cathodehray tubes similar, to the cathode ray tube 36, and are connected in these'condand third sectionsQrespectively, of the transmission lirie'24v in substantially the same mannerY as the tube `36,7 tcept that their grids are bypassed to vgroundVV and the control signalsare applied to their cathodes. The cathodes of`tub`es38 and-40 are connected to sources Vof negative potential. (not shown) through resistors 74V and '76,.respectively. f Y Y The lower.V deflection plates 44, 78, 80, etc., ofthe tubes 3.653,8, `4t), etc., are biased progressively less positively by-adjusting'the variable tapon the potentiometers 46, S2, k84, etc., r'espectiv'ely.- VwThus, it will be understood that when nopul'se is travelling down the Vmain transmis- 36, 38, 40 etc., respectively. Also, it will bennderstood that a positive pulse travelling down the transmission line 2 4Y will deileetupon-their respective targets the` electron beamsof ,allfthef tubes Vfor which` the amplitudefof the.

pulsee'xceeds thelbi'as between the deliection plates of the tubes Theorfder numberof the first cathode ray tubeY whose beam,A is-.s'o Vdeiected is Yproportionalto the difference 'betweenthe pulse 'amplitude' being measured and.

the,matiinu'."Qarnplitudepulsey acceptable by 'the pulse amplitude4 analyzer apparatus. For example, if av pulse A- 'tr/Yellingdownithe transmission line 24 is of sulicient amplitude to4 overcome, the'positivebias onthe plate 44-V of thQA't'ubeTZqQY-that is, the potential diierence between the plates42 and `44 is zero,the1electron beam/ of thetube 36 will'k just impinge upon the lower'edge 68 of thetarget v 6,6.and causeconduction throughthe tube 36.A As' acon- Sedan?? atteind. ssifsif; '710- a ssnalisapplrd one 38 and 4i) are substantiallyV triggered control pulse generator 72. The generator 72 may be of any suitable type, such as a monostable multivibrator of conventional design. The output of the generator 72, which may be in the form of the square pulse B, is applied to a scaler 90, through a capacitor 94, and thence to a counter 92, of conventional design, whereby the fact that the pulse A caused conduction iirst in the cathode ray tube 36 is tallied.

It is obvious, with the circuitry and biasing thereof thus far described, that a pulse which is suicient to cause conduction in one of the cathode ray tubes will cause conduction in every subsequent cathode ray tube along the transmission line 24. Thus, since the plates 78 and 8G of the tubes 38 and 40 are biased progressively less positively than the plate 44 of the tube 36, the tubes 38 and 49 will be rendered conductive. Also, since there is a triggered control pulse generator, scaler, and counter connected to each of the sections of the transmission line 24, in a manner similar to the generator 72, scaler 90, and counter 92 in the irst section of the transmission line, all of the subsequent counters will tally. In order to sort pulses, however, it is necessary to tally only once the counter associated with the cathode ray tube which has been rendered conductive iirst. All of the subsequent cathode ray tubes must have their beams cut olf or rendered non-conductive. To this end, there is provided a second or control transmission line 96 and means connecting it to the main transmission line 24.

The control transmission line 96 runs parallel to the main transmission line 24 and comprises a plurality of sections each of which causes the same time delay as a corresponding section of the main transmission line 24. The control transmission line 96 comprises sections of delay lines 9S, 168, 102, etc., either of the lumped or distributed constants type depending upon the bandwidth desired and chosen in the manner well known to the art.

This series of delay lines is connected to each other through cathode coupled amplifiers, one between each pair of adjacent delay line sections. To this end, for example, a cathode coupled amplilier 112, comprising a rst triode 114 and a second triode 116 has the grid of the triode 114 coupled to one end of the delay line 98 through a capacitor 11S, and to ground through a terminating resistor 12d. The anode of the triode 116 is connected to an end of the delay line 109. The grid of the triode 116 is connected to a source of negative potential (not shown) through a resistor 122. The cathodes of the triodes 114 and 116 are coupled by sharing a common cathode resistor 124. The anode of the triode 114 is connected to a source of positive potential (not shown) through a load resistor 166. Resistors 120 and 108 are carefully chosen to be the characteristic impedance of the delay lines with which they are associated so that signals travelling along the control transmission line 96 will not be reected at a cathode coupled amplifier. The i delay line 9S and the cathode coupled amplier 112, and their associated circuitry, comprise one section of the multi-section control transmission line 96. 'I'he second section oi the control transmission line 96 comprises the delay line 181i and a cathode coupled amplifier 128, having substantially the same circuitry as described for the rst section of the control transmission line 96 comprising the delay line 98 and the cathode coupled amplifier 112.

interconnecting means are provided between the main transmission line 24 an the control transmission line 96 to cut oli conduction in all of the cathode ray tubes subsequent to the first one that exhibits conduction as a result of a voltage pulse travelling down the main transmission line 24. To this end the target of the cathode ray tube in each section of the transmission line 24 is coupled to the grid of the second triode in a corresponding section of the control transmission line 96. For example, the target 66 of the cathode ray tube 36 is connected to the grid of the triode 116, through the generator 72, and the capacitor 94. Also, the anode of the rst triode of the cathode coupled amplifier in each section of the control transmission line 96 is coupled to the cathode of the cathode ray tube in the section of the main transmission line 24 subsequent to the corresponding section of the control transmission line 96. For example, the anode of the triode 114, in the iirst section of the control transmission line 96, is connected to the cathode 130 of the cathode ray tube 38, in the second section of the main transmission line 24, through a capacitor 129.

The grid of the tirst triode 114, of the cathode coupled amplifier 112, in the first section of the control transmissionline 96, may be used as an input for negative pulses which render the pulse amplitude analyzer insensitive at desired times. 'Ihis blanking feature may be useful for coincidence or anti-coincidence counting. To this end, a blanking input terminal 132 is connected to the grid of the triode 114, through the delay line 98 and the capacitor 118.V The blanlring input terminal 132 is also connected to the control grid 54 of the cathode ray tube 36, though a capacitor 134.

The operation of the pulse amplitude analyzer, in accordance with the present invention, will now be described. Let it be assumed that the pulse A is a pulse of the largest amplitude that is to be measured. The positive bias on the deliection plate 44 ofthe cathode ray tube 3e is then adjusted so that it will have a voltage substantially equal to the amplitude of the pulse A. The corresponding deiiection plates of the subsequent cathode ray tubes are biased progressively less positive. It will be understood that the cathode ray tube 36 will produce an electron beam which will just impinge upon the lower edge 68 of the target 66 when the diierence in potential between the plates 42 and 44 is zero. Therefore, as the pulse A travels down the main transmission line 24, the cathode ray tube 36 will be rendered conductive when its electron beam strikes the lower edge 68 of the target 66. As a result of conduction through the tube 36, a signal at the target 66 is fed to the triggered control pulse generator 72, and thence to the scaler and counter 92, through the capacitor 94. The counter 92 will tally once the fact that the cathode ray tube 36 has been rendered conductive, thereby sorting and counting the voltage pulse A.

The signal from the target 66 is also fed to the grid of the second triode 116 of the cathode coupled amplier 112, through the capacitor 94. Since this signal emerges from the generator 72 as a positive-going square pulse B, the signal derived at the anode of the first triode 114 of the cathode coupled amplifier 112 will also be positive. This latter positive-going voltage is coupled to the cathode 13d of the cathode ray tube 38 in the second section of the main transmission line 24 through the capacitor 129. The result of the positive-going Voltage on the cathode orc the tube 38 will cut o conduction in the tube 38, that is, its electron beam will not hit its target 144. Thus as the pulse A travels down the transmission line 24, conduction will not be rendered in the cathode ray tube 38, provided only that the time required for the operation of the triggered control pulse generator 72 and 4its resultant action on the cathode ray tube 38 is just equal to the time of transmission of the pulse A from the cathode ray tube 36 to cathode ray tube 38.

A negative-going pulse at the anode of the second triode 116 of the cathode coupled amplifier 112 is also applied to the grid of the first triode 136 of the cathode coupled amplifier 123, in the second section of the control transmission line 96, through the delay line 100 and a capacitor 13S. Consequently, a positive-going voltage will be applied to the cathode 140 of the cathode ray tube ed, through a capacitor 142. The effect of this latter positive-going voltage on the cathode 140 of the cathode ray tube 4d is to cut off conduction in the cathode ray tube 40, provided, again, that the delay line 100 has delayed the control pulse for a time equal to the time of f transmission of the pulse A from the tube 38 to the tube niainvtransnlission line 24, it will' not render the cathode raygtube 49 .conde ii-:ctv'e.V Since the main transmission line Ziantigt-heV `control transmission line 96 comprise a series ofjsubstantially similar multi-sections, respectively, it is now obvious that all cathode ray tubes subsequentito the one that-chas `been rendered conductive will be rendered non-conductiverin the manner explained when the constantslcf rhedelay line sections have been Achosen such that the time of transmission ofY a control pulse for one s,actionalongV the control transmission line 96 is exactly equalto thetimeof transmission of the pulse A for one section: along the main transmission line 24.V Pulse A on the main-transmissionoline 24 and its associated control pulse in the controlntransmission line 96 travel along their respectivetransmission lines side by side each reaching anygone `cathode ray tube at exactly the same time. Thusfit issecnrthatasVtheivoltage pulse A,of maximum amplitude, travels.' down the transmission line 24 it is counted at the'rst section only of the main transmission lin@ ,24,andtallied on the counter 92.. i

VILet `it now be assumed that a second pulse C, of slightly vless*amplitude than the pulse A, follows the pulseiA. 'Tile-.pulse Cf will not apply a sufficiently positive charge on theplate 42 of the cathode ray tube 36in order to Y render Aitjconductive. YIf the pulse C is of an amplitude equal `tfoorcgreater than the positive bias applied to the deection plate 78 of the cathode ray tube 38, it will render the cathode ray tube 38, inthe second'section of the transmission line 24, conductive; that is, the electronbearn Vof `the cathode ray tube 38 will impinge upon itsitarget 144.l Y As a result, 'a signal voltage at the target 144 wllbe applied to the triggered control pulse generator ,146,andV thence to aiscaler 148 and counter 150, throughra capacitor 152. Thus, it is seen that the voltage pulse C--isichannelledthrough the second section of VtheYtransmission line 24, and tallied. The cathode ray tube 4Q=in the section of the transmission line 24 subsequent to the section comprising the cathode ray tube 38, which was just rendered conductive, -is rendered nonconductivejas la result of the positive-going voltage from theigenerator 146 passing through the cathode coupled t amplifier 128,`and applied to the cathode 140 from the anoderof the `first triode 136, through the Ycapacitor-142. In asimilarmanner, conduction in all subsequent cathode rjay tubes V(not shown) in the transmission line 24 is cut oi.

trol transmission line 96 is so designed that its delay per Y sectiqnis exactly thesame as the -delayper section of the Y Y maintrar ismission -line 24; In other words, the delay of thesefcirctiitsis adjusted so that the delay between the output o t one cathode raytube to the cathode of the next cathoderay tube is YjustV equal tothe delay per section o r either vtransmission line. vAs explained, the gain of eac cathode coupled .amplifier may be greater than the unity-so that ineach section the second triode of the cathodecoupled Yampliiier may -be driven from cut oi to satu-rationfand thesignal therefore,;may be of the same amplitude in each/section, there Vbeing no attenuation as it travels down Ythefcontrol. transmission line 96.

fihus, there'phasbeen shown and described a pulse amplitudeanalyzer, in accordance with the objects of the present invention, whereinY the pulses of diiferent'amplitude are sorted -intoseparate channels, and'each channelV counts pulses ofjsubstantially the same amplitude. The pulsearriplituieY analyzer utilizes cathode Iaytubesof relativelysimple design wherein the ,dee'ction sensitivity een; bemadefmuch :greater thanin other analyzer Sys- 1 Vtems because oniyoneedge-of a single target is to Ybe considereglfinsetting the fbiasjfor the. cathode ray-tube. Itjis 'i alsofobvious thatapparatus 'oithej present invention Y does; utilize any Qitcuitry Of, a bandwidth wider than.

'Y'Since Athefcathode coupled ampliiiers V112, 128, etc. Y

thatnreguired rto 'passi theVV unknownY pulses accurately,

Y therebyfproviding apparatus for use in sorting and counting pulses'of high repetition rate.A

YJ\7eclairn i il, nIn a pulseranalyzerLA for sorting pulses of voltage, a main transmission line comprising a klirst series ofY connected sections, a control Vtransmission-line comprising a second series oficonnected sections, means to apply saidV pulses to `said main transmission line onlyiwhereby said pulses are conductedtherealong from section to section, a separate indicating rneans connected cto' each of said sections in said -tirstseriesand responsive to pulses of a predetermined-size, said indicating means in Yeach succeeding sectionibein'g responsive to pulses of progressively smallerramplitude, means cooperatively associatedwith each of said sections infsaid first Vseries to render one of said indicatingmeansoperative first in response to a pulse cf predetermined. amplitude, and means connected between V'said main and said control transmission lines to renderinoperativesaid Vindicating means in sections subsequent.V to the section associated with said one of said indicating means. Y v

. 2. In a pulse analyzer for sorting and counting pulses ofvoltage, armain transmission-line comprising a Yiirst series ofV connected (sections, a control transmission line comprising a second series of connected sections, means to Yapply said pulses to said main transmission line only whereby said pulses are conducted therealong fromisection to section, a separate counting means connectedV t0 each ofzsaid sections in said iirst series and responsive to pulses .of a predetermined size, said counting means in each VVsucceeding section being responsive to pulses of progressivelyV smaller .ampiitude, Ameans ccoperativelyassociatedwith each of said sections in said rst series to renderVV one of saidcounting means operative Viirstin response .to a pulseof predetermined implitude, and means Y connected between said main and, said control Ltransmission lines to render inoperative said counting means in sectionssubsequent tothesection associated'with said one of-saidounting means, each of said sections in said second series comprising unidirectional delay means.v

3.V In a pulse analyzer for sorting and counting pulses of voltage, a main transmission line comprising a first seriestoi connected sections, a control transmission lineV comprising aY second series of connected sections, means to'apply said pulses to said main transmissionY line only whereby said pulses are conducted therealong from sec- Vtion to section, a separate counting means connected to each of said. sectionsjin Vsaid first series and responsive to pulses of. a predetermined size,-said counting meansr in each succeeding section being responsive .to pulses Vof progressively smaller amplitude, means cooperatively Iassocate'd with eachfo'f :saidfs'ections in said rst seriesy to` renderlone ofV said counting means operative iirstin yresponse'to a ,pulse of VVpredetermined amplitude, andmeans Y connected between saidy main andrsaid control transmisi sion Ylines toV render inoperative said counting means in sections subsequent .to the section associated with saidV one of said countingrneanaeach ofV said sections in said Yiirs't series ,comprising an inductance and a threshold cir-V Quit havmg capacitance input means, said means cooperat tively', associated with each section to render one of said dijvoltagegafmain, transmission line comprising a Vtirst series of s clonnectedasections, a control transmission line comprising a second series'of connected Vsections,imeans to applyY said Ypulses to` said main transmission line whereby fsaidpulsesare 'conducted therealong'from section itoV Y' section, separateicounting lmeans connected to each off said` scctionsiin said rst series "and responsive to pulses ofi-.fa predetermined. size, Vsaid counting means in eachsue- Y ceeding section being responsive to pulses of progressively smaller amplitude, means cooperatively associated with each of said sections in said rst series to render one of said counting means operative first in response to a pulse of predetermined amplitude, and means connected between said mian and said control transmission lines to render inoperative said counting means in sections subsequent to the section associated with said one of said counting means, each of said sections in said rst series comprising an inductance, a cathode ray tube having an electron gun, a target, a pair of deflection plates, and means to apply operating potentials to said cathode ray tube for rendering said gun operative to project an electron beam therefrom, one of said pair of plates being connected to a point intermediate the ends of said inductance, said means cooperatively associated with each section to render one of said counting means operative comprising voltage bias means connected to the other of said pair of plates, and each of said sections in said second series comprising a delay line and a cathode coupled amplier coupled thereto.

5. A pulse analyzer for sorting and counting pulses of voltage comprising a main transmission line having a plurality of sections, each of said sections comprising an inductance, a cathode ray tube comprising an electron gun, a target, means supplying operating voltages to said cathode ray tube for rendering said gun operative to project an electron beam therefrom, and a pair of beam deflection plates positioned between said gun and said target, one of said plates being connected to a point intermediate the ends of said inductance, voltage bias means connected to the other of said plates, said target having an edge positioned to intercept said beam only when the voltage between said plates is a predetermined value, said other of said plates in the cathode ray tube in each of said sections of said transmission line being biased progressively less positively, a control transmission line having a plurality of sections, each of said last-mentioned sections comprising a delay line and a cathode coupled amplier coupled thereto, means to apply each of said pulses to the input of said main transmission line whereby to cause the electron beam in one of said cathode ray tubes to strike its target first and thereby cause it to conduct, means connected between lsaid main and said control transmission lines and responsive to said conducting cathode ray tube to cut olf the electron beams in the cathode ray tubes in the sections subsequent thereto, and .means for indicating the particular target which intercepts its beam rst.

6. A pulse analyzer for sorting and counting pulses of voltage comprising a main transmission line having a plurality of sections, each of said sections comprising an inductance, a cathode ray tube comprising an electron gun, a target, means supplying operating voltages to said cathode ray tube for rendering said gun operative to project an electron beam therefrom, and a pair of beam deection plates positioned between said gun and said target, one of said plates being connected to a point intermediate the ends of said inductance, voltage bias means connected to the other of said plates, said target having an edge positioned to intercept said beam only when the voltage between said plates is a predetermined value, said other of said plates in the cathode ray tubes in each of said sections of said transmission line being biased progressively less positively, a control transmission line having a plurality of sections, each of said last-mentioned sections comprising a delay line and a cathode coupled ampliier coupled thereto, means to apply each of said pulses to the input of said main transmission line whereby to cause the electron beam in one of said cathode ray tubes to strike its target first and thereby cause it to conduct, means connected between said main and said control transmission lines and responsive to said conducting cathode ray tube to cut off the electron beams in the cathode ray tubes in the sections subsequent thereto, and means for indicating the particular target which intercepts its beam first, each of said cathode coupled amplifiers comprising a first and a second tube each having a cathode, a grid, and an anode, each of said delay lines in each of the sections of said control transmission line being coupled to the grid of said first tube in said amplier in its respective section, and means connecting the anode of said second tube of said amplifier in each section to the delay line in the next succeeding section of said control transmission line.

7. A pulse analyzer for sorting and counting pulses of voltage comprising a main transmission line having a plurality of sections, each of said sections comprising an inductance, a cathode ray tube comprising an electron gun, a target, means supplying operating voltages to said cathode ray tube for rendering said gun operative to project an electron beam therefrom, and a pair of beam deflection plates positioned between said gun and said target, one of said plates being connected to a point intermediate the ends of said inductance, voltage bias means connected to the other of said plates, said target having an edge positioned to intercept said beam only when the voltage between said plates is a predetermined value, said other of said plates in the cathode ray tubes in each 0f said sections of said transmission line being biased progressively less positively, a control transmission line having a plurality of sections connected to each other, each of said last-mentioned sections comprising a delay line and a cathode coupled amplier coupled thereto, means to apply each of said pulses to the input of said main transmission line whereby to cause the electron beam in one of said cathode ray tubes to strike its target first and thereby cause it to conduct, means connected between said main and said control transmission lines and responsive to said conducting cathode ray tube to cut ol the electron beams in the cathode ray tubes in the sections subsequent thereto, and means for indicating the particular target which intercepts its beam first, each of said cathode coupled amplifiers comprising a first and a second tube each having a cathode, a grid, and an anode, each of said delay lines in each of the sections of said control transmission line being coupled to the grid of said first tube in said amplier in its respective section, means connecting the anode of said second tube in said amplifier in each section to the delay line in the next succeeding section of said control transmission line, and said means connected between said main and control transmission lines comprising a separate triggered control pulse generator connected in circuit between the target of the cathode ray tube in each section of the main transmission line and the grid of said second tube in a corresponding section of said control transmission line, and the anode of said lrst tube of said amplifier in each section of said control transmission line being coupled to the gun of the cathode ray tube in a succeeding section of said main transmission line.

References Cited in the le of this patent UNTED STATES PATENTS 2,412,467 Morton Dec. 10, 1946 2,449,819 Purington Sept. 21, 1948 2,529,666 Sands Nov. 14, 1950 2,589,130 Potter Mar. 11, 1952 2,593,948 Wiegand Apr. 22, 1952 

